Prefabricated metal-frame knockdown work table



P, COHEN 2,731,316

CKDOWN WORK TABLE Jan. 1?, 1956 PREFABRICATED METAL-FRAME KNO FiledApril 22, 1954 INVENTOR. PHILIP COHEN 0% ran ATTORNEY United StatesPatent PREFABRICATED METAL-FRAME KNOCKDOWN WORK TABLE Philip Cohen,Philadelphia, Pa. Application April 22, 1954, Serial No. 424,870 8Claims. (Cl. 311-4) The present invention relates generally toindustrial work tables or the like and it relates more particularly toprefabricated knock-down work tables.

An object of the present invention is to provide a novel constructionfor an industrial work table or the like, having a relativelyinexpensive prefabricated knock-down metal frame which can be compactlypackaged for convenience in storing and shipping and which can bequickly and easily assembled to give a strong, rigid structure capableof standing up under heavy industrial use. Another object of the presentinvention is to provide a table of the character set forth wherein aseparate sectional top can be separately packaged and subsequentlyquickly and easily mounted upon the frame, with its edges fully enclosedand protected by the frame and with novel fastening means for securelylocking the top sections to the frame in abutting end-to-endrelationship.

A further object of the present invention is to provide a prefabricatedknock-down work table having a frame made up of individual standardelements, of pressed steel or the like, capable of being compactlypackaged for convenience in storing and shipping, which can be quicklyand easily assembled to give a continuous, more or less rectangularframe which is sturdy and rigid and capable of standing up under heavyindustrial use. Still another object of the present invention is toprovide a table of the character set forth having a separate twopiecetop of non-warping plywood panels or the like,

with novel means for securely locking the top panels to the frame inabutting end-to-end relationship, with the outer edges of the top panelsfully enclosed and protected by the metal frame.

Still a further object of the present invention is to provide a new anduseful construction for a prefabricated knock-down metal frame worktable having novel structural elements or aprons of pressed steel or thelike capable of being secured to corner supporting legs or the like andhaving inwardly-directed bottom flanges to facilitate the connection ofsway-braces thereto, and also having outwardlyand upwardly directedgenerally L- shaped flanges capable of meeting to form a rnitre cornerand adapted to enclose and protect the outer edges of separate toppanels of plywood or the like;

Another object of the present invention is to provide a prefabricatedknock-down metal frame work table with novel spline means for securing apair of separate nonmetal top panels to the frame in abutting end-to-endrelationship. Other objects and advantages of the present invention areapparentin the following detailed description, appended claims andaccompanying drawlngs.

In my Patent No. 2,605,150, granted July 29, I have shown a sectionaltable made up of metal frame elements of pressed steel or the likecapable of being shipped in completely knock-down form, in relativelysmall packages. In the construction of my aforesaid patent, thestructural elements ran be readily assembled to give a frame sectionwhichis adapted to receive and support a non-warping wooden top; anynumber of such sections being capable of assembly in end-to-endrelationship, so as to give a work table of any desired length. Theconstruction of my aforesaid Patent 2,605,150 has proven particularlyuseful where tables of relatively great length (as for example tablesranging in length from 50 feet to several hundred feet) are needed, asfor example in the garment industries.

However, Where relatively shorter tables are needed (as for exampletables having a length of 8 to 16 feet), I have found that it is moreconvenient and less expensive to provide structural frame elements whichwill fully enclose and protect all of the outer peripheral edges of theseparate plywood or other non-metal top panels and which are capable offorming a right-angular mitre corner.

According to the present invention, I have perfected a novelprefabricated knock-down metal frame work table having structural framemembers designed particularly for use in relatively shorter lengthtables, as aforesaid, and constructed and arranged to provide thedesired mitre-corner and top panel protection.

I have also perfected a novel spline connection whereby two separate toppanels of plywood or other nonmetal can be securely connected, inabutting end-to-end relationship, to intermediate transversely extendingmembers forming part of the metal frame.

For the purpose of illustrating the invention, there is shown in theaccompanying drawings one form thereof which is presently preferred andwhich has been found in practice to give satisfactory results; it beingunder stood, however, that the present invention is not limited to theprecise instrumentalities and arrangements illustrated, and that theseveral structural. elements can be variously arranged and organizedwithout departing from the spirit or essential attributes of theinvention.

Referring to the accompanying drawings in which like referencecharacters indicate like parts throughout:

Figure .l is a perspective view of a table forming one embodiment of thepresent invention; parts being broken away better to reveal theconstruction thereof.

Figure 2 is a fragmentary vertical cross-sectional View, on an enlargedscale, taken generally along the line 2-2 of Fig. 1.

Figure 3 is a fragmentary enlarged perspective view showing one cornerof the frame, as it appears before installation of the top panels.

Figure 4 is a fragmentary perspective view showing the centerpart of theframe, including the cross members, as it appears before installation ofthe top panels.

Figure 5 is a fragmentary perspective view showing the frame of amodified embodiment of the present invention, in which the centersupporting legs are eliminated.

One embodiment of the present invention is shown gen erally in Fig. 1.In this embodiment, may provide a prefabricated knock-down generallyrectangular frame made up of a number of parts, formed of pressed sheetsteel or the like, to be more fully described hereinbelow, which arecapable of being compactly packaged for convenience in shipping andstoring, and which can be quickly and easily assembled into a strongrigid supporting structure, capable of standing up under heavyindustrial use.

The main metal frame elements of the embodiment of Fig. l are asfollows: six substantially identical legs 20,

of which four are located at the corners and two are located at thesides; a center top cross bar or brace 22 connecting the upper ends ofthe center legs 20 in a manner to be more fully described hereinbelow;three lower cross bars or braces 24 connecting the corner legs and thecenter legs respectively in a manner to be more fully describedhereinbelow; two end frame members 26; and two pairsof left and rightside frame members 28 and 30 respectively. a I

Each of the legs 20 is of generally U-shaped channel cross-section, asbest shown in Figs. 3 and 4, with the main web or base 32 disposed atthe side of the table and with the parallel sides. 34. directedinwardly. An extensible" vertically-slotted foot 36, also of U-shapedcross-section, is adjust-ably connected. at the lower end. of eachleg'2'0' by means, of bolts 36. to permit the height of the table. tobevaried somewhat and also to permit compensation for unevenness of thefloor.

The lower cross bar 2.4,, which are also of U-shaped cross-section butwith a slightly narrower web, are adapted to be, fitted. snugly within,the. flanges 34 of the legs 20 and. to be secured to, the legs somewhatabove the extensible feet 36 by bolts 42 extending through alignedopenings in the: leg flanges. 34. and the brace. flanges 44, asbestindicatedin Fig. 4.

The. center top. brace. 22. which is also of U-shaped crossrsection. hasa plurality of, spaced openings 46. formed in its web 48;, the flanges.50 extending downward from the web. The two ends, of the. center topbrace 22 are bent at right angles so: as to provide a pair of downwardlydirected portions 52 intended to fit over and enclose the uppermostends. of the center legs.

The end frame members26. have a main vertically disposed web 5.6 withan: inwardly directed generally horizontal flange 58 formed at the loweredge thereof. At the upper edge of the webv 5.6. there is formed anintegral generally L-shaped flange having an outwardly directedgenerally horizontal portion 60 and an upwardly directed generallyvertical portion 62, as best shown in Fig. 3. v

The web 56 is constructed and arranged to fit outside of the endmostflange 34 of. each of the corner legs 20 and tobe connected thereto by apair of bolts 64 which extend through. aligned openings in the twomembers, as indicated in Fig, 3. The inwardly directed lower flange 58terminates somewhat shortv of the ends of the web 56 to accommodate theaforementioned corner leg flange 34,

as also indicated in Fig. 3.

the end of the side frame members as will be more fully describedhereinbelow.

A diagonal sway-brace66 is bolted, at one end, to the endmost flange 34of the corner leg 20, and at the other end, to. the lower flange 58 ofthe end frame member 26, as shown in Fig. 3, so. as to provide a morerigid connection between each end of the frame. member 26 and thecorresponding corner leg 20.

A plurality of spaced holes 68 are provided in the outwardly extendingportions 60 of the L-shaped top flange to permit the table top to beconnected to the frame member in a manner to be described hereinbelow.

Each of the left. and. right side frame members 28 and 30 has avertically disposed web 70, an inwardly directed lower flange 72, and anupper generally L-shaped flange including an outwardly directed,generally horizontal portion 74- and an upwardly directed generallyvertical portion 76, so that the side frame members have generally thesame cross-section as the end frame members, as best indicated in Fig.3.

The web 70 of each of the side frame members 28 and 30 is adapted tooverlie the. web 3.2 of the corresponding corner leg 20, and, is.secured thereto by a plurality of bolts 78., the lower flange 7, 2:terminating somewhat short of the end of the web 7010, accommodate theinnermost flange 34- of the leg; as. indicated in Fig. 3..

'The end. of the: outwardly extending portion 74. of the L-shapedtopflange is' cutv at a 45-deg-ree angle so that it forms. a QQ-degree.miter. corner. with the corresponding end of the adjoining, frame member26-.

p The. centermost. ends. of the left. and right side frame members. 28and 30 are square, cut andare adapted to meet in end-to-end relationshipgenerally at. the center of, and overlying the downwardly bent end 52 ofthe center top brace 22. Four bolts 54' extend through aligned openingsin the web of each of the side frame members 28 and 30, the downwardlybent portion 52 and the upper end of the center leg, so as tointerconnect the aforesaid elements, as best shown in Fig. 4.

The centermost ends of the lower flanges 72 of the left and right sideframe members 28 and 30 are cutback somewhat to accommodate the centerleg, as indicated in Pig. 4.

A pair of diagnal sway braces connect the two flanges 34 of each centerleg to the lower flange, 72 of the corresponding side frame member 28 or30; the ends of the sway braces being suitably bent to abut the flangeand being secured thereto by bolts, rivets or other suitable fasteningmeans.

A second pair of diagonal sway braces 82 connect the two flanges 34 ofeach center leg to the corresponding flanges 50 of the center top brace;the ends of the sway braces 82 to the center leg flanges 34 by the samebolts.

or other fastenings which secure the lower ends of the sway braces 80 tosaid flanges 34. This not only expedites assembly but also serves togive an extremely rigid and strong connection intermediate the sideframe members, the center leg and the center top brace.

Thus, the use of two pairs of sway braces which are angular-1y related(the braces 80 extending generally laterally and upwardly, while thebraces 82 extend generally inwardly and upwardly) and which are securedto the center leg flanges at identical points gives a more or lesscontinuous reinforcing structure which has proved to be extremelyeffective in withstanding both lateral and transverse stresscs, andwhich can stand up under many years of hard use to which work tables arecustomarily subjected in industry.

I prefer to provide a pair of rectangular top panels 84 of non-warpingplywood or other suitable non-metal. As indicated in Fig. l, the twopanels 84 are generally rectangular and, when placed in end-to-endabutting relationship, fit snugly within, the rectangular frame formed62 and 76, so that, when installed on the assembled frame. 7

as indicated in Fig. 1, the top panels will have their upper surfacessubstantially flush with the upper edges of the top flange portions.

in order. to provide a secure and non-shifting interconnection at theabutting edgesof the top panels 84, I provide said edges with splineslots 86 running along the entire length of said abutting edges. A metalspline 38, best shown in Fig. 4- and' having threaded. holes 90corresponding to the opening 46 in the. web. 48 of the center top brace22 is constructed and arranged to be fitted within the juxtaposed slots86' and to be tightened to the center top brace 22 by means of aplurality of threaded bolts 92 directed upwardly through the openings 46and engaging with the'h oles 90; the unde'rsideof each of the therebyconverting the two top panels into what is virtually a single continuousuninterrupted and continuous the two top panels are secured to the topflange portions that, when the spline88 is fitted into the er-k.

60 and 74 by a plurality of screws 96, shown in Fig. 4, directedupwardly through holes 68 and 98 formed in said portions 60 and 74.

All of the metal frame elements of my novel table can be placed in acompact package of relatively small crosssection and of a length justsuflicient to accommodate the longest frame elements, which are usuallythe side frame members 28 and 30 and/or the end frame members 26. It israther common to construct industrial work tables so that their lengthis about double their width. In such case, the length of the end framemembers and the side frame members is about the same, since there aretwo of the latter on each side. This obviously makes for greatercompactness and efliciency in packaging. The two plywood top panels 84are, of course, separately packaged in side-by-side relationship so asto give a thin, fiat, easily handled item, which can be convenientlyshipped and stored.

In Fig. 5, there is shown a modified embodiment of the novel table ofthe present invention, which is adapted particularly for use in smallersizes than the embodiment of Fig. 1.

This embodiment resembles that of Fig. 1 except in those particulars setforth below. Thus, as shown in Fig. 5, in this embodiment the centerlegs and their connecting braces are eliminated and, in place of thehalflength side frame members 28 and 30 described above, I provide fulllength side frame members 29 which have the same cross-sectionalconfiguration, with a vertical web 70, an inwardly directed lower flange72, and a generally L-shaped top flange including an outwardly-directedportion 74 and an upwardly-directed portion 76; both ends of theoutwardly-directed portion 74 being cut at a 45-degree angle so that90-degree miter corners are formed with the end frame members 26.

In this embodiment, a single, full-length non-warping top panel 85 isprovided, in place of the two half-length top panels 84 of Fig. 1. Thereis, of course, no longer any need for the center spline connection; thesingle top panel 85 now being peripherally secured to the frame members26 and 29 by screws passing upward through the holes 68 and 98, in themanner described hereinabove.

The foregoing embodiments are to be considered, in all respects, merelyas illustrative and not restrictive; reference being made to theappended claims as indicative of the scope of the present invention.

Having thus described my invention, I claim as new and desire to protectby Letters Patent the following:

1. A knock-down table comprising a generally rectangular non-metalnon-warping top; and a prefabricated sectional frame of pressed steel orthe like, said frame including four generally vertical corner legs ofU-shaped channel cross-section with a main web disposed at the side ofthe frame and with a pair of inwardly-directed flanges one of which isdisposed at the end of the frame, a plurality of end frame members andside frame members extending generally horizontally between the upperends of the corner legs and detachably secured thereto, each of saidframe members having a generally vertically disposed web and a topflange of generally L-shaped cross-sectional configuration with ahorizontal outwardlyextending portion of substantial width and avertical upwardly-extending portion, means for releasably securing theends of the side frame members to the outer face oft he main web at theupper end of the corner leg, means for releasably securing the ends ofthe end frame members to the outer face of the endmost leg flange at theupper end of the corner leg, the corner ends of the outwardly-extendinghorizontal portions being cut at 45-dagree angles so that the adjoiningends of the end frame members and the side frame members meet to form90- degree miter corners, the upwardly-extending flange portions forminga generally continuous frame into which the top is adapted to fit insnug generally flush relation- 6 ship; and means for releasably securingthe edges of the top to the underlying outwardly-extending top flangeportions.

2. A construction according to claim 1 wherein the frame includes agenerally vertical center leg intermediate the corner legs on each sideof the frame, there being two half-length frame members on each side ofthe frame with their center ends detachably secured to the upper end ofthe center leg in aligned end-to-end relationship, the upper ends of thetwo center legs being connected by a top brace which extendstransversely of the table and also serves to support the table top.

3. A construction according to claim 2 wherein two pairs of diagonalsway braces connect each center leg to the top brace and to thehalf-length side frame members respectively.

4. A construction according to claim 3 wherein each of the legs is ofU-shaped cross-section with inwardlydirected flanges, and wherein thetop brace is of inverted U-shaped cross-section with downwardly-directedflanges, and wherein one pair of diagonal sway braces extend upwardlyand inwardly from the flanges of each center leg to the flanges of thetop brace while the other pair of sway braces extend upwardly anddivergently from the flanges of the center leg to the lower edge of thetwo halflength side frame members, both pairs of sway braces beingsecured to the center leg flanges at the same points to give acounter-braced structure.

5. A construction according to claim 2 wherein the top is made up of twohalf-length panels with their center edges disposed in abuttingrelationship above, and supported by, the top brace, and whereinfastening means detachably connect the abutting center edges of the toppanels to each other and to the top brace.

6. A construction according to claim 5 wherein the fastening meanscomprise a spline constructed and arranged to fit into aligned groovesformed along the abutting center edges of the top panels, and aplurality of threaded bolts or the like constructed and arranged toextend upwardly through openings in the top brace and to make adjustableengagement with the spline, the abutting edges of the top panels beingrecessed along their under sides to accommodate the bolts, tightening ofthe bolts operating to cause the spline to pull the abutting edges ofthe top panels together and also locking said abutting edges securely tothe top brace.

7. In a table having a prefabricated generally open frame includingvertical corner legs and generally horizontal end and side membersextending intermediate the upper ends of the legs and including a topbrace extending transversely generally at the center of the frame, saidtable having a separate top made up of two half-length panels with theircenter edges disposed in abutting relationship above, and supported by,the top brace; fastening means for detachably connecting the abuttingedges of the top panels to each other and to the top brace, saidfastening means comprising a thin flat elongated spline constructed andarranged to fit into aligned grooves formed along the abutting centeredges of the top panels somewhat below the top surface of the panels,and a plurality of individual connecting elements extending upwardlyfrom the top brace and making adjustable engagement with the splinewhereby tightening of the connecting elements causing the spline to pullthe abutting edges of the top panels together with the spline concealedthereby and also locking the abutting edges securedly to the top brace.

8. A construction according to claim 7 wherein the individual connectingelements comprise threaded bolts or the like which extend upwardlythrough openings in the top brace, and wherein the abutting edges of thetop panels are recessed along their under sides to accommodate thebolts.

(References on following page) References Cited in the file of thispatent UNITED STATES PATENTS Gorsline Nov. 13, 1923 Wedge July 15, 1930Rosenberg July 18, 1939 Rosenberg July 18, 1939 Bales Feb. 9, 1943

